Gas and lots of soot?

[andym79]

Hi guys, I am new to reloading the 6.5X55, I loaded up around 100 rounds for my 1913 Carl Gustav. The first 14 shoots were fine, on the 15th however I felt a little gas come out rearward of the bolt. When I extracted the case it was covered in soot!

I would have said this was due to low pressure, but I weighed each charge and double checked them!

The load was a 140gn cast bullet, using H4198, 21gns and a gas check!

Winchester brass, the cases were neck sized only after previously being fire formed!

Could the brass (all from the same batch, and reloaded the same number of times, twice on that particular cartridge have been thicker and not expanded enough to seal in the chamber?

Any ideas why this should happen?

I have not used the rifle in a weak for fear that the problem lies with the bolt!

[hardy]

Hello Andy,assuming all your powder is dry and primers are new production and seated fully,the only thing that springs to mind is powder positional sensitivity.Look up" Dacron". as a filler,plenty of posts here,Basically it locates the powder up against the primer for consistent ignition.One other thing is that the cast boolit base is seated below the neck and lube has migrated into the powder,contaminating it and causing a squib.Dacron protects against this happening.Good luck .I,m sure a zillion other possibilities will be along shortly.Cheers Mike

[swheeler]

Yup and that puff of gas comes back right on your shootin' eye ,doesn't it. Low pressure did not let the brass obturate the chamber neck. Use some dacron filler with the 4198 or switch to a faster powder. It is possible, but not probable(after 2 firings) that your brass needs the necks annealed, my guess would be poor ignition from powder position or possibly a weak main spring. Let us know what you find.

[Bret4207]

It's possible your brass is work hardened enough that the light load isn't enough to open the brass enough to seal too. Annealing may help. Posts 2+3 cover everything else I can think of. I very, very seriously doubt your bolt is any part of the issue.

[MtGun44]

You can try annealing the neck by holding it in a candle flame, slowly turning it until it is
too hot to hold at the base. Just let it air cool, water cooling does nothing for the hardness,
just makes the case wet.

Bill

[Larry Gibson]

Yup and that puff of gas comes back right on your shootin' eye ,doesn't it. Low pressure did not let the brass obturate the chamber neck. Use some dacron filler with the 4198 or switch to a faster powder. It is possible, but not probable(after 2 firings) that your brass needs the necks annealed, my guess would be poor ignition from powder position or possibly a weak main spring. Let us know what you find.

+1

Larry Gibson

[Squakeag]

I found a sweet load for my 6.5x55 Swede M38 ... 140 cB on 18 grs. of 2400. Problem is the powder tends to bridge in the funnel so one load would be under the next over the 18 grs. Check all the loads watching for bridging in the funnel! Ruined a nice M38 Swedish Mauser that way.

[zomby woof]

I use 17 grains of 4198 along with Dacron for my 140 Swede load.

[David2011]

Oooh! The Carl Gustav is a NICE rifle, and not just by military standards. Mine is a 1918 M96. I like it so well that I built a K98 receiver into a modern 6.5x55 and I love it. I need to try some cast boolits in the M96. The K98 is used for long distance shooting so it only gets J-words. H4895 is one of my favorite powders and can be loaded down to as little as 60% of the maximum published load.

David

[JIMinPHX]

The last time that I ran into that problem, the chamber had a neck area that was several thousandths larger in diameter than it was supposed to be.

[1Shirt]

+2 on Wheelers comments!
1Shirt!